Bomb displacing gear



Oct. 16, 1945.

G. A. BRoNsoN BOMB DISPLACING GEAR Filed Dec. 1, 1942 sheets-sheet 1 ymy y Mm NL T.

mm 5m Am A W m e 6` G. A. BRoNsoN BOMB DISPLACING GEAR Filed Deo.

3 Sheets-Sheet 2` m. R A] 6 md 6 BY g AUTOR/VFY G. A. BRoNsoN l BOMBDIsPLAcING GEAR Filed Dec. 1, 1942 oct. 16, 1945.

3 Sheets-Sheet 3 lll George A Bron/on INVENroR.

BYQQM I ArroR/vfr Patented Oct. 16, 1945 UNlTED wif,

BOMB DISPLACIN G GEAR George A. Bronson, Santa Monica, Calif., assignerto Douglas Aircraft Company, Inc., Santa Monica, Calif.

20 Claims.

This invention relates to a bomb displacing gear for use on an airplanein conjunction with a bomb rack or other bomb carrier which isconstructed to release the bomb at the will of the aircraft operator,and particularly to a bomb displacing gear for use on dive bombingairplanes.

The bomb rack is usually placed in a bomb bay formed in the undersurface of the fuselage, both to keep the plane aerodynamically clean,and to bring the weight of the bombs nearer the level of the center ofgravity of the plane.

In dive bombing, the diving angle is preferably between '70 and 9Udegrees to reduce to a minimum the gravity deviation of the bombtrajectories from the direction of the dive and the consequent need forallowing for this deviation in sighting the airplane for the dive. Thebombs released at the end of the dive, being aerodynamically cleanerthan the airplane, tend to fall more rapidly than the plane. In highangle dives the bomb trajectory after release is nearly parallel to theiiight path of the airplane.

If the trajectory begins at the undersurface of the airplane, there isdanger of the bombs falling into the propeller blades and breaking themor being exploded. Accordingly, devices have been employed to move thebomb upon its release from the bomb rack to a position sufficientlydisplaced outwardly from the fuselage that the bomb trajectory willclear the path of the propeller even in 90 dives.

One such device consists of a swinging structure pivoted to theunderframe parts of the airplane on a transverse axis which is inadvance of the position in which the bomb is carried by the plane. Itsfree end is held in the bomb bay by the bomb trunnions in position tocarry the bomb upon its release from the bomb rack. Upon release of thebomb this free end swings downwardly and forwardly, carrying the bomb ina circular arc to a position substantially displaced below the fuselagewhere the bomb begins its fall to earth. Since the swinging structureacts like a sling, it gives the bomb an outward throw; furtherdisplacing it from the fuselage.

The position of the bomb bay longitudinally of the plane is determinedby the consideration that the bombs, particularly the larger bombs,because of their weight must be located adjacent the transverse axis ofthe airplane so asto keep the airplane in proper balance for nightcontrol. When a displacing gear of the above described type is usedthere is an additional reason for locating the bomb bay longitudinallynear the center of gravity of the plane. This position avoids theunbalancing effect which would be caused by the displacing movement of aheavy bomb mounted near the tail or nose of the air- I plane and theresulting lightening of the weight of these portions.

However, the understructure of a dive bombing plane is often such that.the hinge axis of a displacing structure which is positioned with its'free end opposite a bomb rack disposed centrally of the plane and whichis of a length to sufficienti-.v

ly displace the bomb, would be at a location occupied by otherequipment.

a short fuselage. Thus, a nose wheel may operate across a space whichthe pivoted end yof such a swinging bomb displacement structurev wouldhave to occupy to satisfy the above stated conditions, i. e. that thebomb cannot be carried aft of the center of gravity of the plane, thatthe' bomb should be carried in a bomb bay or close to the body of thefuselage, and that the'radiusv arm of the swinging structure must belong enough to displace the bomb clear of`v the pro'- peller.

It is one object of this invention to provide a' bomb displacing gearwhich is relatively short longitudinally of the airplane with'referenceto the degree of bomb displacement which it effects,A

so that the gear may be pivoted or otherwise secured aft of a nose Wheelor other interfering l plane parts.

It is another object of this invention to provide a bomb displacing gearwhich will place the 'bomb' in the air stream with its longitudinal axisstabilized in a position lying in or parallel to the vertical plane ofsymmetry ofthe airplane, to

prevent lateral trajectory deviations which might with other bombs of acause the bomb to collide salvo.

It is another object of this invention to accomplish the aforesaidobjects by a structure which is safe, dependable and readily operated.

It is another object of this invention to provide a structure which maybe used with similar struc-Hr tures in a battery of two or more Withoutopera-v tively affecting' each other in a Way to prevent'` theaccomplishment of the aforesaid objects.

will act as a sway brace and will remove the This diiculty isA` -f moretroublesome in the smaller planes having` bomb from the bomb bay with aminimum of lateral movement of the bomb, thus permitting the use of abay but slightly wider than the bomb.

Other objects and advantages of the invention will be brought out in thefollowing description taken in connection with the accompanying drawingsand appended claims.

In the drawings-which are for illustrative purposes only: 10

Figure 1 is a perspective view of a two unit displacement gear embodyingthe invention showing one bomb in position in a bomb rack with onedisplacement gear unit in normal positie-niceA neath it and the otherbomb about to belreleasedls from the other displacement gear,..unit.-..;

Figure 2 is a side elevation of one of they arms of the displacing gearshowing a portion of the arm cut away to expose the mechanism'therein.wr

Figure 3 is a rear elevation of the two unit gearflgo with bombs inposition, showingr the bomb bay in phantom lines.

Figure 4 is' a side elevation showing-a one unit displacement Ygear inretracted position;t11e hy= draulic'retracting motor and the bomb .rackas-25 carriagesA showing the' arm'in 'cross section. f 30 Figure ,'7 isa graph .showing the performance characteristics: of :the gearwof this'invention. in s comparison with those of anothertype of displacing;gear.:

Figure 8-is a: side elevation-partly in section of 35 one'oft-liefhydraulicretracting motors.-

Figure 9 is a fragmentary side elevationalviewshowing :the fvalveoperating'. l.mechanism of the hydraulic i'retracting i imo-torn and.v.associated parts. f

Figure'll() is afragmentary. sectional view/taken 40 along-:the line:IIJ-1.10 :ofnFgure 2, show-ingv the.` construction-of .the-devicefor'ilocking thebomb engagingrodfof the displacing gear.

Figurell is a sectional'view-illustrating-theinternal construction ofthe valve mechanism ein-w45 ployedin Aconjnnctionwith ithe retract-ingmotors.-

A two unit .displacement -gear is shown'in Fig# ureswlzand 3; It ismounted-in a bomb baywhich-l is indicated..mphantomin Figure 3 andriesignatedz:bynthevnumeralwI-I.; f' Ea'chfunit lo com-J -50 prisesapairfof :armsI/Z, disposedlongitudinally of the bay and pivoted at I3 bymeansloi -ears-fA I4 onytheforward .ends ofthe arms'to the vframestructurev-of theaircraft-- adjacent the forward end-of theloay .I.I.:The'rear end-of each arm1 has v55 secu-redfthereto fa bumper-I5 which'is formed withia catchy IB which engages 'a latch face-i3 of a latch:arm 4:8a.ifThe latch .arm is pivoted to a: bracket'vl'l :securedlto-thei-frame-structure of the aircraft adjacent the rear end of the bay:60

The 'latch fac'el8 engages .the catch VIt when vthearm\:|2 :is initsuppermost posi-tion in which it is inclinedslightly.upwardly-from-its -pivoted front 'l endeto itslrearslatchedend,the flatch vandv'catchh Figure. e

Eachfarmfconsists-iof atubularA railL I9 'of lboxl like crosssection-(see Figure with-a pair of fittings 420 and.2-I at :itsim'ierend-andthebump-v er I-5 at its outer.z ende -Y Thel'fittings 2D'and 2i are -70 bolted to .the rail I'9 andato each othen'the liit#ting-.20 "beingaextendediinwardly to providefthe@` The fittings ZI areeach-formed hinge ear I4. with vla hub.25'iextendingfr laterally itowardthe other'arm-,of thei-unit. .The hubs 2.5 iare-riveted-'f to the endsof a hollow shaft or tubular housing 26 which thus rigidly unites thearms I2.

As may be seen in Figures 2 and 5 each rail I9 is formed with groovedrunways 2'I and 28 in the upper and lower horizontal walls thereof andhas slidable thereon a bomb supporting carriage 29 comprising sideplates 39 bolted together and providing bearings for a pair of upperrear side vertical-rollers f3 2,.an upper `Vfront Vertical roller 3ltraveling in-the runway 21, a Vlower` front vertical roller 33 and alower intermediate centralrrvertical roller 34 traveling in the runway28, two upper intermediate central horizontal rollers--3v5ytwo-lowerrear central horizontal rollers 39, and fonecloweriront horizontalroller 39a, thesefii'verhorizontal :rollers traveling in the runways 2'Ior 28.1'Ihezrollers are so arranged as to hold the carriageparts spacedfrom the rail surfaces and prevent canting of the carriagelongiitudinallyior transversely.

A heX rod 35 is slidably supported in two nether lugs 3l and 38 on 'thecarriageand may be locked in anyl longitudinal position of adjustmentbya slide 'flocking pin .49 in a vertical passage 4I in thelug-SI asshownl in Figure 10 of the drawings. The pin 40 `'has ay key rib` 42the'upper end 45 of which is spaced from the upper endof the'pin40."This rib engages fluted serrations on the juxtaposed face of the hexrod 35,`-the pinfbeing manually retractable against the action of acompression spring 43 on a key-mounting rod 44 for the purpose offreeing theheX rod from the rib 42 for longitudinal adjustment withrespect to 'the carriage 29.

The rear rend of the hex rod 33 is formed to provide :a rearwardlyopening' fork 46 Awith an upper and lower jaw. between whichmayberreceived--a trunnion 4l of a bomb 49." To prepare an `aircraft fornight with a bomb load abomb is secured'in the bomb rack abovea unit I3.Then thepins of theeunit' +9 'are'pulledfout thev rods-36 are movedforwardly ofthe aircraft; the arms I2 are un'latched'fromthe-latchiarmsie by manually" swinging f the 'latch arms' outwardly, and`the'arms` I2 are 'then'manually' slightlyde`- pressed-to the lfullyhorizontal position shown'in Figure Y1 and in jfull Alines in Figure 2.`'Ih'efork 4S is thenvat a level to enga-ge Vthetrunnionsll'l of a bomb48 suspended-from'ra bombrrack 49 in the bomb bay `I I. The carriage 29'is manually-M held approximately at the level 'to afford this en'-gagement of the trunnions with the forks-46 land the" rodsA 36 are moved-rearwardly" of the"air craft to "seat the 'trunnions properly in thefork* openings, after which the pins 4I) are released forspring'retractionto vlockthe rods 35 yin position:

Each -cable 5I is anchoredat Yone end to the cableattachment-bracket Il,loops` around- 'a pulley'52 carried by the carriage Zland` isfastened-at its-other'end-to the bumper I5. "When a bomb 48 `isreleased-from the bomb rack-49 by -disengaging bomb -attaching'loops'therefrom,fthe weight of the Abomb is applied to 'the' armgl 2 andtheunit swings downwardly,l the increasing-'distance -between the carriage-29 and bracket I'l causing the-cable 5I to pull the car: riage towardthe free rear end-of the unit; Thel length'of the cableis so designedthat Ywhen the unithas swung through an arc of approximately ninetydegrees the'carriage is at thel extreme limit of itsuoutward ytravelyadjacent the bumpers I5 and thecable length is substantially alldisposed'i-n a straight line from the' carriage vto the bracket IL*`Thehinge `axisVA at I3 is so located that 'cables Of' a length as abovedetermined will;

whenthe arms are horizontal, position the forks 48 for engagement withthe bomb trunnions, the position of which is prescribed by the positionof the bomb rack and bomb bay.

To eect retraction of the carriages 29.0n the rails I9 when the unitswings back to its normal initial position after release of a bomb fromthe forks 45 on its downward swing, two cables 55 are employed, each ofwhich is fastened at one end to the `carriage 29, extends along theupper grooved runway 21 to the free end of the rail I9 where it passesthrough an aperture in the rail wall and around a pulley 51 mounted inthe interior chamber 58 of the rail and thence extends within the railchamber toward the pivoted end of the arm.

Near the free end of rail I9, it is connected to a sprocket chain 68which extends to the pivoted Vend of the arm |2 where it passes around asprocket wheel 59 mounted between the fittings 28 and 2|, leaves arm |2through an openingr between these :fittings and is connected to anothercable length BI which extendsl to and is secured to the forward end ofthe carriage 29. A collar 53 fixed on cable 55 near the pulley 51 and astop disk 65 fixed within the rail |9 form abutments for a compressionspring 64 which resists movementof the carriage 29 toward the free endof the rail I9 during outward movement of the unit and retracts thecarriage to its initial position as the unit returns to its initialposition.

The sprocket wheels 59 of the two arms of a unit are i'ixed upon aconnecting shaft 68 rotating inthe hollow shaft housing 25 to ensure thetwo carriages 29 occupying at any moment the same relative positionslongitudinally of the rails I9. Any inclination of the axis of the bombtrunnicns from a position perpendicular to the longitudinal axis of theunit is thereby prevented.

Consequently, and since also the unit arms are rigidly associated andheld perpendicular to the pivot axis i3, the bomb must be held at alltimes as it moves outwardly, with its longitudinal axis steadilyperpendicular to the direction of the transverse axis of the airplaneand lying in or parallel to the vertical plane of symmetry of theairplane depending on whether the bomb is initiallyl transported on theairplane in, orlaterally displaced from, the plane of symmetry of theairplane. Stabilized in this positionl the axis of the bomb is less aptto wobble and depart from a smooth curved trajectory lying in a singleplane and consequently less apt to collide with other bombs releasedapproximately at the same time in a salvo.

The displacing gear unit is retracted from its outward ypendent positionby a hydraulically motivated device indicated in general by the numeral18 (see Figures 4 and 8') A plunger 1| is automatically thrust forwardby a hydraulic reciprocating motor 13 upon arrival of the displacinggear at its pendent position. This plunger pushes forward a lever arm 12on the shaft housing 26 to elevate the unit until the catch l5 engagesthe latch face I8 of the latch arm |811 and holds the unit'in itsuppermost idle and unloaded position. The motor 13 and plunger 1| permitsubstantially free downward movement of the arms l2 when, after the bombdisplacing gear is again placed in operative position with the bombtrunnions seated in the forks 45, the bomb is released from the bombrack.

The motor 13 comprises a cylinder 14 and a piston 15. VThe piston 15 hasextending th'erefrom an elongated pneumatic cylinder 16 con- 14, thecylinder 18 having a sealed sliding joint with the cylinder 14 at 11. Anelongated annular chamber 18 is enclosed between the cylinders 16 and14. Y

As best shown in Figure 8, the plunger 1| comprises an outer end 19pivoted to the lever arm 12 and a. pneumatic cylinder 88 whichtelescopically slides within the cylinder 16, the cylinders 16 and 88being of approximately the same length and the cylinder 88 having asmall air escape aperture 8| near its outer end.

Fluid under pressure is admitted to and exhausted from the right end ofcylinder 14 throughA within the valve casing 83 may be turned by meansof a valve stem 88 to occupy either a first position (shown in fulllines) in which' conduits 84 and 85a, and conduits 85 and 86 areconnected, or a second position (shown in dotted lines) in whichconduits 85 and 84, and conduits 86 and 85a are connected. The valvestem 88 is turned by a Geneva movement mechanism 88, the pin |88 ofwhich is carried by a projection 8| on the arm l As the arms I2 drop,upon the release of a bomb, toward a pendent position, the arm 12 ismoved to the right moving the plunger 1| from a normal position shown infull lines in Figure 9 to the transitional position shown in dottedlines in that figure, the latter position corresponding to that shown inFigure 8.

When the arms l2 in their downward swing have traveled a small anglewhich may be adjustably set between 10 and 25 degrees, the Genevamovement 88 turns th'e valve stem 88 admitting fluid under pressure tothe right face of piston 15 and exhausting fluid from the chamber 18causing the piston to move to the left. The cylinder` 18 thereuponbegins a leftward movement toward cylinder 88 which is moving totheiright. The restricted size of inlet opening 82 prevents too rapid amovement of the cylinders toward each' other. Obturation of aperture 8|further slows relative movement of the two cylinders toward each other,cylinder head 15 finally engaging the right end of cylinder 88, the twocylinders moving together to the right under the gravity action of thebomb. As soon as the bomb leaves the forks 46 of the displacing gear,the hydraulic pressurev to the right 0f piston 15 moves both cylinders88 and 16 to the left, the compressed air between the cylinders pushingcyl- K inder 88 ahead of cylinder 16, and the cylinder centricallyspaced from and within the cylinder `or oth'er bombicarryingfmeam arexed in posislowlyzbronght". to atmosphericrpressurez by spas-1..: 'lsageafof fairnithroughz thenaperture'sfBIiL Y Whenthedisplacing gear isnext usedito dropzw a bomh;tthe:weightvof the-.bomb overcomessthezf airpressure between the pneumatic cylinder: v5 endsrthedisplacing fgear.`dropping .unde-r a measi uren-'of pneumaticnloadoto abombe'dischargingzs pendentzposition, vobturatoniof :the aperture. V81|cushioningrthelgeartto anioscillatory lstop'at fan anglerof y90".:orless to thelongitu'dinaliaxis :of the -10 plane:dependingz uponthe'1position-'at rvvhich' the bomb is discharged. .Airisforcedfromzi-,he aperturerfl prionto obturation of thataperturexandianyxresidual air-pressure within the cylinders .16 i" I anditill:aftereobturationcacts to assisttheui'd 15 pressuregrwhichcis at zonce.brought to 'bear uponf 1 chamber 118;; in elevating. the4 now: unloaded.fg'ear y The'ndisplacing :gearfwhen f in Iii-tsl horizontal. IoperatiYemositionin which the bomby trunnions1'20 areaengaged by:.thefforks-A ffacts. :as a supple-'h mentary z sway inraceuforl the;xbomb. suspended from the bomb rack. 'Ilieiforksfd prevent-rotation'almovement-'of `thefbomb aboutfitslaxis andM the :inner sid'exfaces .ofvthe fork :arms/of vthe twof=2 forkssare; :proximately adjacent'. thesides' of the bomb.;

Figure-7. is .a graph :illustratingl.the-'path-of *f movement-.fofaibombiin .the displacing gear; f` Inl thisgraphgdiierent'positionslofthelarms 'I2 of Y 30 the -gear f-:are: :represented byr the.' numerals12a', I2;,-I2ci|2d",IZB,V |21?, :I2g.;i IZB; is thefpositi'on'of thearmsxin the initial latched' position of the gear.v I2g is the extremeposition of the arms at the-W end:.of the-operative movement: ofthegearr' InA 35 termediate' positions-.'I2b5fl2, fIZdgz I2e and VI2fare approximatelyat ,the angles 15i30g 459,' 60"-Tand` '7 5respectively.: z The corresponding Y positions of the=icable1i5l :areshown :in .thedrawings IV The' hingexis'of .thefarms'vis letteredfl3'as-.inthe 40 structural figures.

'Ih'e-.curved'line'l represents the lpath.r of travelv of theforks'46,a'fof the bombzltrunnion sea-ted thereineand'of azfbombr48'4carriedl thereby".I rThe arcuate.` line :92 `represents the quartercircle path Y of travel-of the 1bumper I5 which is also the -path f oftravel of a bombr48f? in 'bombdisplac'ement gears. of presentlyused:types-in which the forksl tionilongitudinally 'of the :arms and Y attheirV -outer ends; and in which thegbombiis displaced in acircularoarcuate path iaboutxthe hinge axis ofthe arms .as apenterf"Comparing'the ftravel: path linesI 9 I 'and 92,thefollowinglsimilarities' and :differences-arenoted The Apointbfseparationv of the bomb from i the f trunnion forks-for anygivenLangleofdive is a v littlebeyond that-angular position'of the arms with respectto theflongitudinal axis `of the plane i at which thearmsf havea true`horizontal" posiw60 tion; for it s at that position. that thegjavvsy ofthe fork begin to incline. olownward1y.-l .'For a 45.- angledive thisangular yposition of the arms is' the I 45 position for .both types ofdisplacing gear. Dx represents the lateral displacement andar?.5the'forward ydisplacement of the .bombJI8- at thev moment of separationfrom the forks on line 9i andf Dyand'dy 1the lateral and forwarddisplacements of bomb 48" at the moment vof sepa-V ,.f rationfon line92.I Gx, grr, Gy and yy represent o the-corresponding Ydisplacements fora 90 dive. A study of these vdisplacement values shows that a gearof'this invention gives an adequate lateral-displacement 'for'anygivenangleof dive andxgives.` a forward. :displacement 'ofsubstantial#V '35 small.` radius and the llinefl being curvilinear witha muchl'onger -radius' means that bomb *48"1 is givena strong outwardcentrifugal throw upon release especiallyfat high angle dives" whereasbomb 48" leaves the forks-'With a negligible'outward movement. Obviouslyaiming at a target is a simpler matter in the -latter case, sincel noal-' lowance` need be made for this centrifugal throwVA` at thebeginning of thebomb trajectory;

I claim:

1. Ina bomb displacing'devicev for use'with'a i releasing bomb supporton anz aircraftgthe com.- bination of: an arm structure 'pivoted onanaxis transverse of the aircraft and 'forwardly' of the... position ofthe supported bomb to be angularly movable downward from and upward to apOSi-L' tion adjacent said'b'omb support; a' bombcarrying meansmovaolycarried byfsaid arm struc ture; and means `interconnecting 'saidbombearrying meansv and. saidl airplane whereby said bomb carrying meansis moved on said arm struc--M ture outwardly from and inwardly towardanin-A ner position/therealong adjacent .the axis'of said..

pivot in correlationwith'downward and upward l movement respectively'ofsaid arm structure, said Y bomb carrying means being so constructedand,... arranged when at its inner positionand when-.. said structure isangularly adjacent saidbomb...

support to receive said bomb upon. release from..

bination of an arm structure .pivoted .on and.

axis transverse of the aircraft and forwardly of the position of thesupported bomb to be angue larly movable downward from and upward to aposition adjacent said bomb support; a bomb carrying means movablycarried by said. arm` structure; and means interconnectingsaidbombcarrying means and said airplanewherebysaid bomb carryingy means .ismoved inwardly .and outwardly on said arm structurel a major.ipor tionof the length of said armv structure. in correlation with downward andupwardmovement .1. respectively of said arm structure; said-bombcarrying means beingfso constructedand arranged when at its innerposition andwhensaid struc-w ture is angularly adjacent said bombsupport to receive saidbomb uponrelease from said-bomb support, and whensaid structure isat ani-angular downwardly positionand. said. bombvcarrying a means is at anoutward position to releasesaid` bomb.

3. In a bomb displacing device I-for usevrith a releasing bombsupportonan aircraft, the combination of: an arm structure` pivoted on anaxisAtransverse .of theaircraftand forwardly-of theif position of thesupportedbomb to be angular1:yf,

movable downward from andupward to a posi-fI i structure in correlationwith downward and upward movement respectively of said-arm structure,said bomb carrying means being so constructed and arranged when at itsinner position and when said structure is angularly adjacent said bombsupport to receive said bomb support and when at an outward position andwhen said structure is at an angular'downward position to release saidbomb.

4. In a bomb displacing device the combination of: a downwardly andforwardly swinging structure pivoted to an aircraft on an axistransverse to the longitudinal axis of the aircraft; a bomb supportmeans longitudinally movable on said structure; andmeans'interconnecting said bomb support and the aircraft whereby saidsupport means is longitudinally'moved on said structure responsive toand simultaneous with downward movement of said structure, saidlongitudinal movement being from an initial position adjacent said axisand inwardly remote from the free end of said structure to a positionradially outwardly therefrom over a distance which is a substantialportion of the length of said structureA and which substantiallydisplaces the centers of curvate movement of the bomb support withrespect to the aircraft forwardly from said axis, said support being soconstructed and arranged as to release a bomb as said structure swingsdownwardly and forwardly. v

5. The combination defined in claim 4, and in which the interconnectingmeans comprises: a pulley means on said bomb support means: and aflexible strand means fixed at its one end to the aircraft at a leveladjacent that of said axis at a point more remote from said transverseaxis than the normal position of the pulley, looped around said pulleyand fixed at its other end to the outer end of said structure.

6. The combination defined in claim 4, and in which the interconnectingmeans comprisesta pulley means on said bomb support means; and aflexible strand means fixed at its one end to the aircraft at a leveladjacentthat of said axis at a point more remotefrom said transverseaxis than the normal position of the pulley, looped around'said pulleyand fixed at its other end to the outer end of said structure, saidstrand means being of a length to dispose said carriage at the outer endofsaid structure at an extreme positionv thereof substantiallyperpendicular tothe aircraft axis.

7. The combination defined in claim 4 and in addition thereto; resilientenergy storing means on said structure and connected to said bombsupportfor storing energy-from said bomb support vmeans as it moves outwardlyon said structure duringthe fall of said structure when loaded witha-bomb and for releasing said energy to return said bomb support meansto its initial position on said structure after release of said bombfrom said structure.

said pulley and fixed at its other end to the outer-1 end of saidstructure; and in addition thereto, resilient energy storing means onsaidstructure `and connected to said bomb support for storing energyfrom said bomb support means 'as it moves, outwardly on said structureduring the fall of said" structure when loaded with a bomb and forreleasing said energy to return said bomb support means to its initialposition on said structure after v"release of said bomb from saidstructure as peran axis transverse of the longitudinal axis of theaircraft; a bomb support movably mounted on said arm structure; meansinterconnecting the support and said aircraft for moving said bombsupport radially ,outwardly in a continuous synchronous relation withthe angle of said down- Ward swing of said larm structure as the sameswings downwardly kabout its axis, said support being so constructed andarranged as to release the bomb when the arm structure is in a downwardposition. o

10. The combination defined in claim 9 in which the bomb supportcomprises a pairv of rearwardly opening forks each having verticallyalined jaws for engaging the trunnions of a bomb.

' 11. In a bomb displacing device for use with a; bomb releasing rack onan aircraft for supporting a bomb longitudinally of the aircraft andwith a bomb on said rack provided with trunnions on opposite sides lofthe bomb: a pair of arms hinged on a transverse axis forwardly of theposition of the trunnions; a, rearwardly opening yoke carried by eacharm in position to embrace the corresponding trunnion, when said armsare in an upper position; means for elevating said arms to said upperposition', said means being arranged to permit downward swing of saidarms, by the weight of a bomb released from said rack; a longitudinallymovable carriage on each arm for mounting a corresponding one of saidyokes; and control means for the carriages correlatively andprogressively responsive to the radial position of the arms forpositioning the carriages initially adjacent the said axis when the armsare adjacent the bomb rack and subsequently adjacent the free ends ofthe arms when the armsare directed outwardly from the aircraft.

12. In abomb displacing device for use with a bomb releasing rack on anaircraft for supporting a bomb longitudinally of the aircraft and with abomb on said rack provided with trunnions on Vopposite sides of thebomb; a pair of arms hinged on a transverse axis forwardly of theposition of vthe trunnions; a rearwardly opening yoke carried by eacharm in position to embrace the corresponding trunnion', when said armsare in an upper position; means for elevating said arms to said upperposition, said means being arranged to permit downward swing of saidarms, by the weightofa bomb released from said rack; a longitudinallymovable carriage on each arm for 'mounting a corresponding one of saidyokes; a pulley on each carriage; and a pair of flexible strands eachconnected lat one end to the aircraft structure rearwardly of theposition of said trunnions and at a point more rearwardly remote fromthe trunnions than the normal position of the pulleys, passing aroundthe corresponding 'pulley rizo,

and `secured at the other end to the free'end of the correspondingl arm.

'13.,The combination defined in claim 12 and in addition thereto: apulley'at the free end of each arm; a transverse shaft rotatably mounted`and"a pair of flexible strand connectors, each secured at one end toone of said carriages, passing tors at a point between the associatedsprocket Wheel and pulley; a stationary spring abutment on each of saidarms adjacent the associated sprocket wheel; and a compression springseated between said movable abutment and said stationary abutment.

GEORGE A. BRONSON.

